Abstract

High temperature seal glass has stringent requirement on glassthermal stability, which is dictated by glassnetwork structures. In this study, a based glass system was studied using nuclear magnetic resonance, Raman spectroscopy, and x-ray diffraction for solid oxide cell application purpose. Glass structural unit neighboring environment and local ordering were evaluated. Glassnetwork connectivity as well as silicon and boron glass former coordination were calculated for different ratios. Thermal stability of the borosilicate glasses was studied after thermal treatment at . The study shows that high content induces and structural unit ordering, increases glass localized inhomogeneity, decreases glassnetwork connectivity, and causes devitrification. Glass modifiers interact with either silicon- or boron-containing structural units and form different devitrified phases at different ratios. -free glass shows the best thermal stability among the studied compositions, remaining stable after thermal treatment for 200 h at .

Received 10 June 2008Accepted 14 July 2008Published online 06 October 2008

Acknowledgments:

This material is based on work supported by the Department of Energy under Grant No. DE-FC07-06ID14739. The help of Mr. Charles Farley, Department of Geoscience, Virginia Tech during Raman spectroscopy experiment is highly appreciated. The authors also would like to acknowledge Professor Robert Bodnar, Department of Geoscience, Virginia Tech for his suggestions during Raman spectroscopy experiment, and Professor Sabyasachi Sen, Department of Chemical Engineering and Materials Science, University of California, Davis for the NMR experiment.